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    <title>Document</title>
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    <script>
        var arr = [1, 2, 2, 2, 2, 3, 3];
        var arrOne = [1, 2, 2, 2, 2, 3, 3];

        console.log(arr.indexOf(2, 5));
        console.log(arr.lastIndexOf(2, 3));
        console.log(arr.toString());
        console.log(arr);
        console.log(arr.join('000'));
        console.log(arr.splice(0, 3));
        console.log(arr);
        console.log(arr.concat(arrOne));
    </script>
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